14 March 2011

Why do baseball players use hGH: Part II, The Science

Last time, I wrote about how and why players use PEDs. Included in that post was highlighting how sometimes players are ahead of the science (arguably steroids) and at other times behind the science (i.e. urinating on your hands, rubbing your bats with ham bones, and arguably steroids). Somewhat blind assumptions, halo effects, and mob mentality tend to shape an uninformed perspective more so than what experts say is likely or know to be true. I forget where I saw this and cannot seem to find it, but a study that surprised me was a study that consisted of telling participants various surprising facts. These facts were differentiated in that some were attributed to "experts" and others were just given. Participants were more likely to accept surprising facts from non-expert sources. So . . . maybe there is a fourth effect, which is perhaps a societal suspicion of scientific literature, which I think would be largely due to a misunderstanding of the scientific method. People often want definitive answers and there are awfully few laws in science. Anyway, this is going on a tangent.

However, with all that being said . . . that players are using something to give them a competitive edge is a great reason to investigate on the efficacy of the treatment. Sometimes lacking a full comprehension of something does not prevent someone from discovering something new. What many baseball players have become are alchemists. Alchemy had its usefulness as it encouraged the works of many, such as Isaac Newton and Paracelsus. It also fostered some silly beliefs such as all things could be turned into gold. So, it may be that baseball players and others have actually hit gold on hGH.

In today's article, I'll be reviewing (or, more aptly, summarizing) several articles about hGH and its effect on athletic performance.

Where did the hGH craze begin?
In 1990, an article was released by Rudman et al (New England Journal of Medicine) in which twelve elderly men ranging in age between 61 and 81 years old were injected with hGH at a concentration similar to what would be found in young adult males for six months. The twelve subjects were found to have about a ten pound increase in lean muscle, a seven pound decrease in fat, and denser bones. The conclusion stated that these effects were like a ten to twenty year reversal of aging. An eager medical and pharmacological community aware of the future elderly care scenarios with baby boomers embraced the possibilities suggested by this article. It also resulted in a boom of pseudoscience and pseudomedical claims and clinics advertising assumed benefits of hGH. Claims have included that hGH improves eyesight, removes scars, renews interest in sex, resurgence of hair growth, increase in muscle strength, increase in stamina, and deepening of one's voice. These benefits extended well beyond the boundaries of the scientific data, claiming that hGH could inhibit processes that lead to aging. However, these claims tend to ignore several follow up studies that dispute their proclamations.

A good summary of follow up studies was provided by Mary Lee Vance in the New England Journal of Medicine in 2003:

A recent double-blind, placebo-controlled study involving 27 women and 34 men, 68 to 88 years of age, who were given growth hormone or placebo for 6.5 months confirmed the effects of growth hormone on body composition; there was no change in muscle strength or maximal oxygen uptake during exercise in either group.3 This study corroborated the findings of a study by Papadakis et al. involving 52 healthy men, 70 to 85 years of age, who were given placebo or growth hormone for six months. Not mentioned on the “antiaging” Web sites is a study of 18 healthy men, 65 to 82 years of age, who underwent progressive strength training for 14 weeks, followed by an additional 10 weeks of strength training plus either growth hormone or placebo. In that study, resistance exercise training increased muscle strength significantly; the addition of growth hormone did not result in any further improvement. Going to the gym is beneficial and certainly cheaper than growth hormone.

Ok, so it is fairly well shown that hGH does not seem to help the elderly increase functional strength, but we can probably agree that an elderly population may not be equal to a younger one. After the jump, we'll review the literature highlighting studies on hGH use in athletes and young adults. This short review will consist of an example of one of the many studies showing no difference, the only study showing a difference, a couple review papers, and expert testimony from the congressional hearing a couple years ago. I could have written a far longer piece going over a couple dozen studies, but figured that excess would not convince anyone one way or the other more than the review papers do. I also figure the review papers provide a stronger summary than I can at this moment.

Where there is a major review of literature, I did not write up individual studies and let the review speak for them. However, there are a few studies I would like to highlight, some reviews, and some expert testimony.

In this study, groups of 15 men and 15 women were further split into high, low, and no dose groups. This means 5 men received a placebo, 5 received a low dose (0.033 mg/kg.d, and 5 received a high dose (0.067 mg/kg.d). These doses were administered over the course of four weeks. Participants were assessed for their oxygen uptake while using a stationary bicycle, power output, blood pressure, heart rate, and ECG. They found that while body weight increased, there was no statistically significant increase in performance (i.e. oxygen uptake, power output).

This is typical for a general study done on hGH. The population size is rather small and the exposure duration is pretty limited. That said, I do not know if baseball players cycle their hGH. They might. In that case, a four week exposure might make sense. What gives this study a bit more power is that these results are continually found in every study done, except one. And that study was released last year . . .

In this study, 63 men and 33 women with an age of 27.9 +/- 5.7 years old were included. The participants were trained athletes with intense workout regimes for a year prior to the study. The men were seperated in groups that included placebo, testosterone (250 mg/wk intramuscularly), growth hormone (2 mg/d subcutaneously), or testosterone and growth hormone. The treatment phase lasted eight weeks with a six week depuration phase. Metrics included body composition characteristics (i.e. fat mass, lean mass, extracellular water mass, and body cell mass) and performance (i.e. endurance, strength, jump height, and bicycle sprint capacity). Growth hormone alone was found to decrease fat and increase lean body mass. However, when administered alone this increase was explained by water retention, but with the addition of testosterone the increase was then explained by body cell mass. At the end of the eight weeks, bicycle sprint capacity did significantly increase with administration of growth hormone and was not related to the testosterone injection. This improvement quickly dissipated and was gone by the end of the six week depuration phase. Endurance, strength, and jump height were not affected. This research was funded by the World Anti-Doping Agency.

This is a fascinating study as it is the only one that has shown hGH having an effect. Ken Ho's group is one to pay attention to with respect to how hGH may be used. It is also interesting in that a previous platform presentation of this work had shown an increase in jump height and nothing else. At least, that was what I remember, but I cannot seem to find it. I think that was released in 2007, so this probably a different study and this current one appears to have a much larger sample size. All of this does not mean this current study is wrong, just that I think we need to tread carefully here as it might be a false positive. What I also find confusing is this statement:

“We found the enhancement in sprint capacity would correlate to a 0.4 second improvement over 10 seconds in a 100- meter dash,” said Ken Ho, Garvan’s head of pituitary research and a co-author of the study, in a statement. “This improvement could turn the last-place finisher in the Olympic finals into a gold medal winner.”

These are the words of a researcher who does not know how to speak to the media or one who knows exactly how science writers just juicy stories. Conditional words are used here and the sentences themselves are not problematic, but I think when lay people read that . . . it does not appear as conditional as it should appear. Ho uses a bicycle sprint test called the Wingate test. This is poorly related to sprinting from what I understand. I'm not sure why he would make this statement. It really colors the science a bit and that is unfortunate. In a later article, Ho steps back a bit from those statements and writes:

...“we do not know how an improvement in Wingate test performance translates to performance in the sporting field,” our speculation of what this might mean in a sprint event is based on mechanistic and conceptual extrapolation.

Regardless, I think the difference seen in hGH effects for sprinting is something to note and register. However, like any study, we need to verify this with future studies. From what I remember of his past reports, this one had a different result than those and it may simply be the case of a false positive. We also should not ignore it. This could be the first piece of a larger group of evidence. However, it does not appear strength or endurance is improved.

They note that no study prior to the publication of this journal article demonstrated that there was any connection between the administration of hGH and any athletic performance metric. They highlight how patients with acromegaly have significantly greater muscle mass than normal individuals, but that this does not translate into an increase in strength. In order words, muscle gained from high levels of hGH has not been shown to increase strength in these individuals. This is similar to findings using trained athletes. However, the authors do note that it is possible that in actual use that athletes take concentrations that would not be permissible in a research trial. There would also be significant adverse risk from these dosages and is a reason why they are not typically allowed in research trials.

This review included all studies published until October 2007 from three comprehensive article databases. The authors were able to find 27 unique studies on hGH dosing (36 +/- 21 g/kg per day) running from one day up to three months (20 +/- 18 days) that focused on young adults (27 +/- 3 years old). Participants in these studies experienced an increase in lean body mass, but strength and exercise capacity did not appear to improve. Fatique and soft tissue edemas appeared more frequent in those dosed with hGH. The authors note that the claims of hGH improving athletic performance is not supported by the literature even though it appears it does affect body composition. They also note that it should be recognized that the treatment regimes used in these study most likely do not reflect real world usage and that adds uncertainty.Expert Testimony: From the last congressional hearing...

Four research doctors testified and all agreed that hGH does not appear to significantly improve athletic perfprmance, but that more research is needed on hGH. Thomas Perls said to the committee, "There is no credible scientific evidence that growth hormone substantively increases muscle strength or aerobic exercise capacity in normal individuals."

Conclusion

As I wrote in the previous post about hGH and PEDs, it would be absurd to think either side has a definitive answer. I think it is also fair to say that those who say that hGH has no discernible effect on performance have the weight of the evidence with them. Several peer-reviewed articles back up that perspective with little mechanistically saying otherwise. There is one study with human subjects that states otherwise. It is a weak position at the moment for those who say hGH certainly improves performance. I think we have also shown that just because a group does something does not mean it works. We are all aware of groups of people doing things that have no bearing on future events. Whether you are burning an ox at the alter, rubbing your bat with a ham bone, or urinating on your hands to prevent blisters . . . none of these are likely going to affect the future. All of these have been devout beliefs of many. Belief does not equal reality. However, sometimes belief is nestled in with reality and beliefs should not be rejected out of hand. As such, we should continue to look at hGH with an inquisitive mind, but we need to be more open and comfortable that the evidence is not there for us to truly label it as a performance enhancing drug. This does not mean that it is not one, it means that there is not enough evidence to say it is. One study and mob mentality has difficulty overturning the rest of the scientific literature out there.

4 comments:

While I certainly agree that we should let facts and scientific evidence drive our beliefs about the relationship between performance enhancing drugs (in this case HGH) and performance, I really don't think there's any good scientific evidence available that speaks to baseball performance and HGH. I think the cited studies show that HGH does not improve raw strength, endurance, and possibly not even speed (depending on how you interpret Ho's operationalization of sprint capacity), but I am not comfortable interpreting these findings to make conclusions about baseball performance, an analytically different concept. I think the media narrative about PEDs has fixated on strength while overlooking other POSSIBLE benefits of PEDs such as HGH. The fixation on strength is understandable given the nation's fascination with the McGwire and Sosa home run race in the late 90s. But I suspect players are not taking HGH for the sole purpose of bulking up in order to allow them to hit 50 home runs or hit 99 mph on the radar gun. For example, Andy Pettitte claims he took HGH to heal from an elbow injury faster rather than bulking up so he could improve his fastball (http://sports.espn.go.com/mlb/news/story?id=3156305). And I think here lies the real "performance" benefit of HGH rather than focusing on raw strength and endurance. I suspect players take HGH due to the belief that it helps stays them recover from minor injuries faster and keeps in shape better. While this initially may not seems like "performance" enhancing benefit, I think that view seriously underestimates the performance value of keeping your body in shape to handle the grind of a 162 game season. It stands to reason that minor injuries which aren't enough to land the player on the DL (or media stories) could affect performance negatively. Being able to manage and conquer this problem is a significant advantage if you believe in the assumption that a healthier player would play better than a player suffering from various minor ailments. Pettitte is not the only player that I've heard tout the recovery properties of HGH. I believe Jason Grimsley used HGH to recover from TJ surgery in almost record speed. Thus HGH could be in a PED not in the sense that it improves your baseball skills (e.g., hitting for more power or dialing up your fastball), but rather it enhances the player's performance by allowing them to capitalize on their bodies fully. Now I should point that is no scientific evidence actually showing (or disproving) this. And for this reason, I believe the direction of public discourse should move from whether using HGH is cheating to scientifically investigating whether HGH has useful healing properties in regards to injuries (not just endurance issue as tested by the cited studies) and, more importantly, figuring a way to regulate HGH in a SAFE manner so it could be incorporated into the game. Thus HGH should be seen as a performance enhancer in way that getting lasik surgery is a performance enhancer. Anyways, that's my two cents. Thanks for the reviewing the scientific literature on HGH. Your hard work is appreciated as always.

While I certainly agree that we should let facts and scientific evidence drive our beliefs about the relationship between performance enhancing drugs (in this case HGH) and performance, I really don't think there's any good scientific evidence available that speaks to baseball performance and HGH. I think the cited studies show that HGH does not improve raw strength, endurance, and possibly not even speed (depending on how you interpret Ho's operationalization of sprint capacity), but I am not comfortable interpreting these findings to make conclusions about baseball performance, an analytically different concept. I think the media narrative about PEDs has fixated on strength while overlooking other POSSIBLE benefits of PEDs such as HGH. The fixation on strength is understandable given the nation's fascination with the McGwire and Sosa home run race in the late 90s. But I suspect players are not taking HGH for the sole purpose of bulking up in order to allow them to hit 50 home runs or hit 99 mph on the radar gun. For example, Andy Pettitte claims he took HGH to heal from an elbow injury faster rather than bulking up so he could improve his fastball (http://sports.espn.go.com/mlb/news/story?id=3156305). And I think here lies the real "performance" benefit of HGH rather than focusing on raw strength and endurance. I suspect players take HGH due to the belief that it helps stays them recover from minor injuries faster and keeps in shape better. While this initially may not seems like "performance" enhancing benefit, I think that view seriously underestimates the performance value of keeping your body in shape to handle the grind of a 162 game season. It stands to reason that minor injuries which aren't enough to land the player on the DL (or media stories) could affect performance negatively. Being able to manage and conquer this problem is a significant advantage if you believe in the assumption that a healthier player would play better than a player suffering from various minor ailments. Pettitte is not the only player that I've heard tout the recovery properties of HGH. I believe Jason Grimsley used HGH to recover from TJ surgery in almost record speed. Thus HGH could be in a PED not in the sense that it improves your baseball skills (e.g., hitting for more power or dialing up your fastball), but rather it enhances the player's performance by allowing them to capitalize on their bodies fully. Now I should point that is no scientific evidence actually showing (or disproving) this. And for this reason, I believe the direction of public discourse should move from whether using HGH is cheating to scientifically investigating whether HGH has useful healing properties in regards to injuries (not just endurance issue as tested by the cited studies) and, more importantly, figuring a way to regulate HGH in a SAFE manner so it could be incorporated into the game. Thus HGH should be seen as a performance enhancer in way that getting lasik surgery is a performance enhancer. Anyways, that's my two cents. Thanks for the reviewing the scientific literature on HGH. Your hard work is appreciated as always.

Thanks for the detailed thought. I very much appreciate the discussion.

My understanding of hGH is that although it is used to increase healing rates in the elderly that the healed tissue is not as strong as tissue that is healed under normal circumstances. This is fine for the elderly who need to quickly reform tissue to be able to avoid infection and return to some level of ability to ensure mobility. An athlete though would not benefit from this kind of quick healing because of the strain he would place on his tissues.

I think sometimes there is confusion about strength meaning strength meaning strength or healing meaning healing meaning healing. The truth under many circumstances is that what works in one situation may actually give poor results in another. One plus is that if a player is incredibly invested in hGH working in an emotional sense, then he will likely have lower cortisol levels which may improve tissue growth.

I think there are a lot of questions to explore. If I was an athlete looking for an edge though...this would not be a direction I would look. There is just scant evidence that hGH may work for athletes. It just does not seem very useful at all.

nganIn review 2 it states"They also note that it should be recognized that the treatment regimes used in these study most likely do not reflect real world usage and that adds uncertainty." Are ballplayers "going for it" and using massive doses? Has any player spoken to this? Thoughtful and informative essay. Thank you.

Contact Camden Depot

We look forward to your questions as well as any suggestions you may have for us.

Additionally, we are always looking for new contributors, so if you want to write for the Depot then e-mail us with an example column that you think fits the tone of the site.

Contributors

Jon Shepherd - Founder/Editor@CamdenDepotStarted Camden Depot in the summer of 2007. By day, a toxicologist and by night a baseball analyst. His work is largely located on this site, but may pop up over at places like ESPN or Baseball Prospectus.

Matt Kremnitzer - Assistant Editor@mattkremnitzerMatt joined Camden Depot in early 2013. His work has been featured on ESPN SweetSpot and MASNsports.com.

Matthew Cassidy - WriterMatt joined Camden Depot before Spring Training in 2017. His love of music is surpassed only by his obsessions with food (unhealthy) and baseball statistics (totally healthy).

Patrick Dougherty - Writer@pjd0014Patrick joined Camden Depot in the fall of 2015, following two years writing for Baltimore Sports & Life. He is interested in data analysis and forecasting, and cultivates those skills with analysis aimed at improving the performance of the Orioles (should they ever listen).

Nate Delong - Writer@OriolesPGNate created and wrote for Orioles Proving Ground prior to joining Camden Depot in the middle of 2013. His baseball resume includes working as a scorer for Baseball Info Solutions and as a Video Intern for the Baltimore Orioles. His actual resume is much less interesting.

Avi Miller - Writer@AviMillerAvi is a SABR enthusiast who is interested in data-driven analysis. His worked has previously appeared on the Baltimore Sports Report.

Matt Perez - Writer@FanOfLaundryMatt joined Camden Depot after the 2013 season. He is a data analyst/programmer in his day job and uses those skills to write about the Orioles and other baseball related topics.

Joe Reisel - WriterJoe has followed the Norfolk Tides now for 20 seasons. He currently serves as a Tides GameDay datacaster for milb.com and as a scorer for Baseball Info Solutions (BIS). He is computer programmer/analyst by day.

Ryan Romano - Writer@triple_r_Ryan writes about the Orioles on Camden Depot and is the editor at Beyond the Box Score. He previously wrote on Birds Watcher and on Camden Chat that one time

Joe Wantz - WriterJoe is a baseball and Orioles fanatic. In his spare time, he got his PhD in political science and works in data and analytics in Washington DC.